[api] add API for Promise status and result.

src/code-stub-assembler.cc

 // Copyright 2016 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 #include "src/code-stub-assembler.h"
 #include "src/code-factory.h"
 #include "src/frames-inl.h"
 #include "src/frames.h"
 
 namespace v8 {
 namespace internal {
@@ skipping 8322 matching lines @@
       LoadContextElement(native_context, Context::PROMISE_FUNCTION_INDEX);
   Node* const initial_map =
       LoadObjectField(promise_fun, JSFunction::kPrototypeOrInitialMapOffset);
   Node* const instance = AllocateJSObjectFromMap(initial_map);
 
   return instance;
 }
 
 void CodeStubAssembler::PromiseInit(Node* promise) {
   StoreObjectField(promise, JSPromise::kStatusOffset,
-                   SmiConstant(kPromisePending));
+                   SmiConstant(v8::Promise::kPending));
   StoreObjectField(promise, JSPromise::kFlagsOffset, SmiConstant(0));
 }
 
 void CodeStubAssembler::PromiseSet(Node* promise, Node* status, Node* result) {
   CSA_ASSERT(this, TaggedIsSmi(status));
   StoreObjectField(promise, JSPromise::kStatusOffset, status);
   StoreObjectField(promise, JSPromise::kResultOffset, result);
   StoreObjectField(promise, JSPromise::kFlagsOffset, SmiConstant(0));
 }
 
@@ skipping 13 matching lines @@
                        Heap::kUndefinedValueRootIndex);
   StoreObjectFieldRoot(result, PromiseReactionJobInfo::kDebugNameOffset,
                        Heap::kUndefinedValueRootIndex);
   StoreObjectFieldNoWriteBarrier(result, PromiseReactionJobInfo::kContextOffset,
                                  context);
   return result;
 }
 
 }  // namespace internal
 }  // namespace v8